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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Technical Advice => Topic started by: Graeme on February 01, 2009, 03:04:30 PM
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This may be a silly question but as per the standards any area of habitable space under 1m2 can be ignored from minimum dBA levels.
What about a cupboard that a person is not likely to spend much time in,probably with the door open and over 1m2 but under 60m2 ?
i.e a cleaners cupboard or store. would these come under unhabitable therefore ignored?
Thank you.
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Well if it anywhere near 60m sq I think i would class it as habitable...
Personally I think risk assessment and common sense prevails.... a store room "under the stairs" 15m sq obviously not habitable due to low ceilings etc i wouldn't consider.
An actual small room 15m sq used for storeage eg an archive room stacked floor to ceiling obviously used by employees might only have a "habitable walkthrough" of 5m sq (1 m wide x 5 m long ) but still say 60db.
I don't think all the "leave the door open" business works in practical terms.
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i know the leave the door open bit is n/a but i.e a cleaners cupboard with sink that is roughly 2m2 but probably not enough room to shut yourself in whilst using the sink. habitable or not? bearing in mind the defination of habitable is providing conditions which are good enough to live in.
so the room you mentioned with 5m2 walk thorugh-would you class that as habitable?
might be reading too much into it but is a store room habitable?
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I would think that if it was a cleaners room where they refill buckets etc it would need to have a fairly high sound level incase they happen to be filling buckets at that time the alarm is sounded.
As a rule of thumb, if i see a room that is definately only a walkin cupboard I would relax the sound level to 60dbs give or take a bit however if it has some sort of function I.E cleaner sink or washing machine or some other working function I go for 65dbs min.
Just my opinion
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I would think that if it was a cleaners room where they refill buckets etc it would need to have a fairly high sound level incase they happen to be filling buckets at that time the alarm is sounded.
Just my opinion
Thanks Thomas and Dave. I suppose you could apply the 30 sec rule and running water to the cleaners cupboard.
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I thought the 'flushing of the toilet' the old D.S used to pull on d/b test went out the window , perhaps CT can let us know when he is around.
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it did. i meant ignore the running water in the cleaners cupboard and ignore any background noise if likely to persists fot 30 secs or less.
The standards have ignore running water from bathrooms an toilets so i tke it would include a cleaner filling up a bucket for 20 seconds.
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I'd go for that one Graeme.
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One square metre was just a round number that occurred to us in passing. People really should not read codes so prescriptively. An element of intelligent reading is sometimes necessary. We do not write codes for numpties, but for competent persons.
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. We do not write codes for numpties, but for competent persons.
i take it that was aimed at me Colin? i do apologise for being a thick engineer.
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Graeme, from one 'thick' engineer to another ;) I'm sure CT was not having a go at you only! I've noticed that his posts are invariably trying to teach us all not to get so caught up with the precise figures in recommendations.
All of us with a reasonable understanding of fire alarm systems must be able to be prepared to recognise where a variation from a recommendation is not unsafe. In this vein, the recent BS's have included a number of areas of flexibility where, previously, 'codehuggers' would have a field day. For example, limited areas of 60dba SPL in areas otherwise recommending 65dba. (another is mounting heights of mcps)
At the end of the day none of the recommendations should be considered as 'written in stone' for an experienced system designer/installer.
This can go both ways. For example, whilst BS might not recommend a requirement for a minimum db level for areas less than 1m2, if such an area existed and was used as a 'security officers' booth, it is highly likely that a suitable alarm db level would be required.
Commonsense and experience actually determines the requirements in most cases, rather than the BS recommendations.
Therefore should it be considered that the BS recommendations are only provided as a set of rules for those without the necessary experience/commonsense and as an approximate guide to others?
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Graeme, from one 'thick' engineer to another ;) .
Therefore should it be considered that the BS recommendations are only provided as a set of rules for those without the necessary experience/commonsense and as an approximate guide to others?
Thanks Wiz
that would have been a better way to put it.
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you only ever get criptic clues with CT
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you only ever get criptic clues with CT
...unless it's your round!
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Graeme, Not aimed at anyone. Just a shorthand way or reminding people that it is expected that people use commonsense in applying BSs. People just make up figures as a yardstick and then find that the world is measuring them to the 99th decimla point. It is all very frustrating.
Buzzard, I recall trying to tell you at Thomsons Garage that it was your round but you were so agog in respect of the girl with the body that I had to buy them myself. So dont tell me about clues regarding whose round it is!
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Now,I bought the first one - admittedly however,certain distractions did knock any further such actions on the head!
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Graeme, Not aimed at anyone. Just a shorthand way or reminding people that it is expected that people use commonsense in applying BSs. People just make up figures as a yardstick and then find that the world is measuring them to the 99th decimla point. It is all very frustrating.
Ok Colin thanks. I can understand your frustrations but it's only because we are wanting to get everything 100% as some training courses put the wind up you with all the weight on the commissioning engineers shoulders.
They take the opposite view to BS in that we do have to check everything including the design and install. I go by BS now as i got into alot more hassle their way by never getting away from jobs with all the stuff i highligted.
The job this thread is based ,i have taken all dB(A) readings and submitted them back to the consultant for him to make the decisions and as you say common sense would dictate no need for sounders in some rooms measured.
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Graeme, I have now included a system of rating 'non-compliance' items to my commissionings. I highlight everything that doesn't comply precisely to the recommendations of BS but then highlight those 'which in my professional opinion are of no detriment to the proper operation of the system'. This might, for example, include a detector sited only 450mm rather than 500mm from a wall etc. etc.
It is the 'interested parties' responsibility, and not mine, to decide if strict compliance with the letter of BS recommendations is necessary, but I would hope my comments would give them the confidence not to insist on the designer/installer making loads of unneccesary minor adjustments.
However, the reason I highlight even the most minor of BS digressions is so no 'smart arse' later tries to insist I have missed something on my commissioning! No-one outwizzes the Wiz!
It is right that the training courses make it clear that everything should be checked carefully. If not, a major ommission might occur.
You should be able to prove that you checked everything by highlighting every problem, no matter how small. But you should also be able to point out which of those small problems are of no serious consequence.
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Thanks Wiz
That's exactly what i have done on this site and many(variations) were brought to attention before installation started.
Graeme